Synthesis of novel donor–acceptor manganese( I ) complexes of ferrocenylacetylene: crystal structure of [(C 5 H 5 )Fe(C 5 H 4 )CCMn(CO) 3 {Ph 2 PCH(Me)CH 2 PPh 2 }] which has potential for second-order non-linear optics

Three novel manganese(I) ferrocenylacetylide complexes have been synthesised and characterised and the crystal structure of [(C5H5)Fe(C5H4)CCMn(CO)3{Ph2PCH(Me)CH2PPh2}] has been determined, in which the incorporation of a chiral chelating phosphine leads to crystallisation in the non-centrosymmetric space group P212121.